The need to conserve water is important in many areas. For example, areas that are generally hot, which receive little annual rainfall or little seasonal rainfall or which are subject to periodic droughts and water shortages can suffer from a lack of sufficient water. The lack of water can restrict the ability to provide for purposes such as drinking, domestic or industrial use or agricultural use such as crop irrigation and for other needs.
The storage of water in tanks, dams and reservoirs is one way of ensuring that sufficient water reserves are available for domestic, industrial and agricultural use. However, the evaporation of water from these bodies of water can result in significant losses of critical water resources. In some instances, annual losses of water by evaporation from storage dams can exceed 50% of the water volume.
In an attempt to reduce water evaporation, physical covers that float on the surface of a body of water have been used. However, a problem with such covers is that they are not practical for large volumes of water such as reservoirs and large dams.
In other attempts to reduce water evaporation the formation of thin films or monolayer structures on the surface of water bodies has been described. Such films or monolayers can reduce the rate of water loss to the surrounding atmosphere by creating a barrier between the water body and the atmosphere.
Layer structures such as monolayers can be formed from molecules that possess a polar hydrophilic head group and a non-polar hydrophobic tail. These molecules can align themselves at an air-water interface and self-assemble to ideally form a one-molecule thick layer on the surface of a body of water.
A problem with many monolayer structures however is they do not persist on the surface of the body of water for more than a couple of days. As a result, frequent re-application of the monolayer to the water body is required in order to provide effective evaporation control over a period of time. In addition, the lack of stability of many monolayer structures against wind disruption is also an issue which limits their usefulness in many circumstances.
It would be desirable to address some or all of the problems of the prior art and to provide an effective method for controlling water evaporation.
A reference herein to a patent document or other matter which is given as prior art is not to be taken as an admission that the document or matter was known or that the information it contains was part of the common general knowledge as at the priority date of any of the claims.
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